Dr.
Alois Alzheimer, a German neurologist
(Picture:
US National Library of Medicine)
It's
over than one century since a German physician and psychiatrist,
Alois Alzheimer, observed his patient with suffered loss of memory
and language. She (his patient) also had hallucinations, delusions, and cognitive
impairment.
She
was only 51 year-old and too early to had a dementia, so she was
diagnosed as presenile dementia.
Dr.
Alzheimer identified and described her psychological and behavioral,
then when she passed away, Dr Alzheimer asked her family to autopsy her
brain.
He
took her brain tissue to laboratory and did staining to get observation in
her nervous system. Fortunately, at that time the research methods
using stain was developed.
The
staining was able to visualize the nerve cells.
He
found “dramatic brain shrinkage and abnormal deposits in and
around nerve cells” and
the abnormal deposit in today are called amyloid
plaques and neurofibrillary tangles.
Histopathology
of Alzheimer's diseases
(Picture
from Neuroscience, Purves, et al)
From
the picture, the yellow colors are neurofibrillary tangles, and brown
darks are amyloid plaques. Specifically, they are in the neocortex,
amygdala, and brainstem.
The
causes of Alzheimer's Disease is not fully understand yet.
There
are three principle features could be detected in every person who
severe with the Alzheimer's disease:
- Collection of intra-neuronal cytoskeletal filaments or neurofibrillary tangles, also known as aggregate tau protein in the brain.
- Extracellular deposit of an abnormal amyloid or amyloid plaques.
- A diffuse loss of neurons. The accumulation of neurofibrillary tangles and amyloid plaques lead to death of neuron cells so that the brain became shrinkage.